Heat dissipation device and method of manufacturing same

ABSTRACT

An exemplary heat dissipation device includes a first fin unit, a second fin unit, a heat pipe, a first base and a second base. The heat pipe includes a condensing section extended through the first fin unit and the second fin unit and an evaporating section extending from the condensing section. The evaporating section includes a first heat absorbing portion extended through the first fin unit and a second heat absorbing portion spaced from the second fin unit. The first base is located at one side of the second fin unit and supports the second heat absorbing portion thereon. The second base is covered on the first base. The first and second bases sandwich the second heat absorbing portion therebetween.

BACKGROUND

1. Technical Field

The disclosure generally relates to device cooling, and more particularly to a heat dissipation device and a method of manufacturing the heat dissipation device.

2. Description of the Related Art

Heat dissipation devices are used to remove heat from heat-generating electronic components such as central processing units (CPUs) and others, keeping the electronic components within safe working temperature limits, and enabling stable operation. A typical heat dissipation device includes a base contacting an electronic component and absorbing heat therefrom, a number of fins, and a heat pipe. The heat pipe has one end connected to the base by solder and the other end connected to the fins. The fins dissipate the heat to the ambient environment.

When the heat dissipation device is manufactured, soldering flux must be added between the heat pipe and the base for soldering the heat pipe and the base together. Furthermore, since the heat pipe and the base are usually made of different materials, a nickel-plating process may be required before soldering. Such process materials and manufacturing procedures render assembly of the heat dissipation device somewhat costly and complicated.

What is called for, then, is a heat dissipation device which can overcome the limitations described.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an isometric, assembled view of a heat dissipation device according to an exemplary embodiment of the present disclosure, wherein the heat dissipation device includes a first fin unit, a second fin unit, a third fin unit, a first base, a second base and three heat pipes.

FIG. 2 is similar to FIG. 1, but with the second base omitted.

FIG. 3 is an exploded view of the parts shown in FIG. 2.

FIG. 4 is an exploded view of the heat dissipation device of FIG. 1.

FIG. 5 is similar to FIG. 4, but viewed from another aspect.

FIG. 6 is a cross-section of the heat dissipation device of FIG. 1, taken along a line VI-VI thereof.

FIG. 7 is a schematic view showing one stage in an exemplary method of manufacturing the heat dissipation device of FIG. 1.

DETAILED DESCRIPTION

Reference will now be made to the figures to describe the present heat dissipation device and method in detail.

Referring to FIGS. 1 and 2, a heat dissipation device according to an exemplary embodiment of the present disclosure includes a first fin unit 10, a second fin unit 20, a third fin unit 30, three heat pipes 40, a first base 50 and a second base 60. In alternative embodiments, the number of heat pipes 40 can vary according to particular requirements.

Referring also to FIGS. 3-5, the first fin unit 10 includes a plurality of first fins 11 stacked together. Each of the first fins 11 is almost rectangular, and includes a rectangular main body 110, an extending portion 112 extending upward from a middle portion of a top side of the main body 110, a first flange 1104 extending perpendicularly from a bottom side of the main body 110, and a pair of second flanges 1106 extending perpendicularly from end portions of the top side of the main body 110 (i.e., portions of the top side of the main body 110 other than where the extending portion 112 is formed). Thus the extending portion 112 is narrower than the main body 110. Three first through holes 1102 are defined in a bottom end of the main body 110 of each of the first fins 11. Three second through holes 1122 arranged side by side are defined in the extending portion 112 of each of the first fins 11. The first flanges 1104 of each two neighboring first fins 11 are connected to each other, and regularly space the main bodies 110 of the first fins 11 from each other.

The second fin unit 20 includes a plurality of second fins 21 stacked together. Each of the second fins 21 includes a rectangular main body 210, a pair of ears 212 extending upward from two opposite ends of a top side of the main body 210, respectively, a first flange 2104 extending perpendicularly from a bottom side of the main body 210, and a pair of second flanges 2122 extending perpendicularly from top sides of the ears 212, respectively. The main body 210 of each of the second fins 21 is shorter than the main body 110 of each of the first fins 11. Three first through holes 2102 are defined in a bottom end of the main body 210 of each of the second fins 21. The first flanges 2104 of each two neighboring second fins 21 are connected to each other, and regularly space the main bodies 210 of the second fins 21 from each other. A receiving room 24 enclosed by the ears 212 and the top sides of the main bodies 210 is defined in a middle portion of a top side of the second fin unit 20.

The third fin unit 30 includes a plurality of third fins 31 stacked together. Each of the third fins 31 has the same configuration as each of the first fins 11. More specifically, each of the third fins 31 is almost rectangular, and includes a rectangular main body 310, an extending portion 312 extending upward from a middle portion of a top side of the main body 310, a first flange 3104 extending perpendicularly from a bottom side of the main body 310, and a pair of second flanges 3106 extending perpendicularly from end portions of the top side of the main body 310 (i.e., portions of the top side of the main body 310 other than where the extending portion 312 is formed). Alternatively, the configuration of each of the third fins 31 can be different from that of each of the first fins 11.

Each of the heat pipes 40 is U-shaped, and includes a condensing section 41, an evaporating section 43 parallel to and spaced from the condensing section 41, and a connecting portion 45 connected between the condensing section 41 and the evaporating section 43. The evaporating section 43 includes a first absorbing portion 431 connected with the connecting portion 45, a second absorbing portion 433 extending from a distal end of the first absorbing portion 431, and a third absorbing portion 435 extending from a distal end of the second absorbing portion 433. Each of the heat pipes 40 has a circular transverse cross-section, except that the second absorbing portion 433 has a transverse cross-section generally in the shape of a flattened ellipse. An outer diameter of the condensing section 41 exceeds a diameter of the first through holes 1101 of the first fins 11. An outer diameter of the first absorbing portion 431 of the evaporating section 43 exceeds a diameter of the second through holes 1122 of the first fins 11.

The first base 50 is metal, and is configured for holding the evaporating sections 43 of the heat pipes 40 in position. Three first receiving grooves 51 arranged side by side are defined in a top surface of a middle portion of the first base 50. A length of each of the first receiving grooves 51 is substantially equal to that of the second absorbing portions 433 of the heat pipes 40. Four mounting holes 53 are defined in four corners of the first base 50, respectively. A depth of each of the first receiving grooves 51 is substantially equal to half a thickness of each of the second absorbing sections 433 of the evaporating sections 43.

The second base 60 is approximately H-shaped, and includes an elongated main plate 61 and two aliform plates 63 extending outward from two opposite sides of the main plate 61, respectively. The alifrom plates 63 are longer than the main plate 61, with the main plate 61 interconnected between middle portions of the two alifrom plates 63. The main plate 61 has substantially the same configuration as the first base 50. Three second receiving grooves 611 corresponding to the first receiving grooves 51 of the first base 50 are defined in a bottom surface of a middle portion of the main plate 61. Four locating holes 613 are defined in four corners of the main plate 61, respectively. A depth of each of the second receiving grooves 611 is substantially equal to half the thickness of each of the second absorbing sections 433 of the evaporating sections 43.

Referring to FIGS. 2 and 3 together, when the heat dissipation device is assembled, the first fin unit 10, the second fin unit 20 and the third fin unit 30 are arranged side by side, with the first flanges 1104 of the first fins 11, the first flanges 2104 of the second fins 21 and the first flanges 3104 of the third fins 31 coplanar with each other to cooperatively define a planar bottom surface 12 of the heat dissipation device. The second fin unit 20 is located between the first fin unit 10 and the third fin unit 30. The second flanges 1106 of the first fins 11, the second flanges 2122 of the second fins 21 and the second flanges 3106 of the third fins 31 are coplanar with each other to cooperatively define a frame-shaped top surface 13 of the heat dissipation device. The receiving room 24 is enclosed by the top surface 13 of the heat dissipation device. The extending portions 112 of the first fins 11 and the extending portions 312 of the third fins 31 are located at left and right sides of the receiving room 24, respectively, and above the receiving room 24. Thus, the second through holes 1122 of the first fins 11 and the second through holes 3122 of the third fins 31 are higher than the receiving room 24.

The first through holes 1102 of the first fins 11, the first through holes 2104 of the second fins 21, and the first through holes 3102 of the third fins 31 are communicated with each other. The second through holes 1106 of the first fins 11 and the second through holes 3122 of the third fins 31 are aligned with each other. The first base 50 is received in the receiving room 24, with the first receiving grooves 51 of the first base 50 collinear with the second through holes 1122 of the first fin unit 10, respectively. The heat pipes 40 connect the first fin unit 10, the second fin unit 20 and the third fin unit 30 via the condensing sections 41 being interference fitted in the first through holes 1102, 2102, 3102, and the evaporating sections 45 being interference fitted in the second through holes 1122, 2122, 3122.

Referring to FIGS. 1 and 6 together, the second base 60 covers the first base 50, with the second receiving grooves 611 communicated with the first receiving grooves 51 of the first base 50, respectively. The second base 60 and the first base 50 cooperatively define three receiving holes 65 for the second absorbing portions 433 of the evaporating sections 43 to be interference fitted therein, respectively. The locating holes 53 of the second base 50 are coaxial with the mounting holes 613 of the first base 50, respectively. A plurality of fasteners 70 are respectively extended through the locating holes 53 of the second base 50 and screwed onto the mounting holes 613 of the first base 60 to fixedly connect the first base 50 and the second base 60 together. Thereby, the evaporation sections 43 of the heat pipes 40 are further held in position via the first base 50 and second base 60.

When the heat dissipation device is used, the second base 60 directly contacts an electronic component to absorb heat generated therefrom. Due to the second absorbing sections 433 of the evaporating sections 43 being interference fitted between the first base 50 and the second base 60, the heat absorbed by the second base 60 can be quickly conducted to the evaporating sections 43 of the heat pipes 40. Thus, the heat generated by the electronic component can be quickly conducted to the first fin unit 10, the second fin unit 20, and the third fin unit 30 via the heat pipes 40, to further dissipate the heat into the ambient environment in a timely manner.

An exemplary method of manufacturing the heat dissipation device includes following steps:

Referring to FIG. 7, the first step is to provide the first fin unit 10, the second fin unit 20, the third fin unit 30, three rough heat pipes 80, and the plurality of fasteners 70. The rough heat pipes 80 are different from the heat pipes 40 only in that the second absorbing sections 433 of the rough heat pipes 80 have a circular transverse cross-section.

The rough heat pipes 80 are firstly connected with the first fin unit 10, with the condensing sections 81 interference fitted in the first through holes 1102 of the first fins 11, and the first absorbing portions 431 of the evaporating sections 83 interference fitted in the second through holes 1122 of the first fins 11.

Then the rough heat pipes 80 are connected with the second fin unit 20, with the condensing sections 81 interference fitted in the first through holes 2102 of the second fins 21. The second heat absorbing portions 833 of the evaporating sections 83 of the rough heat pipes 80 are located above the receiving room 24 of the second fin unit 20.

The first base 50 is put in the receiving room 24, with the first receiving grooves 1102 collinear with the second through holes 1122 of the first fin unit 10, respectively. The depth of each of the first receiving grooves 1102 is slightly smaller than half a thickness of each of the second heat absorbing portions 833. A part of each of the second absorbing portions 833 is received in a corresponding first receiving groove 1102 of the first base 11, and another part of each of the second absorbing portions 833 is exposed outside of the corresponding first receiving groove 1102.

Then the rough heat pipes 80 are connected with the third fin unit 30, with the condensing sections 81 interference fitted in the first through holes 3012 of the third fins 31, and the third absorbing portions 435 of the evaporating sections 835 interference fitted in the second through holes 3122 of the third fins 31.

Referring back to FIG. 1, finally, the second base 60 is covered over the first base 50, with the second receiving grooves 611 aligned with the first receiving grooves 51 of the first base 50, respectively. The other part of each of the second absorbing portions 835 which is exposed outside of the corresponding first receiving groove 51 is received in a corresponding second receiving groove 611 of the second base 60. The depth of each of the second receiving grooves 611 is slightly smaller than half the thickness of each of the second heat absorbing portions 833. Due to a sum of the depth of any one of the first receiving grooves 51 and the corresponding second receiving groove 611 being smaller than the thickness of the corresponding second heat absorbing portions 833, the second base 60 is spaced from the first base 50, with a clearance defined between the top surface of the first base 50 and the bottom surface of the second base 60.

The fasteners 70 are respectively extended through the locating holes 613 of the second base 60 and further screwed into the mounting holes 53 of the first base 50, to fixedly connect the first base 50 and the second base 60 together. During this process, the second base 60 presses the second evaporating sections 835 of the rough heat pipes 80 until the bottom surface of the second base 60 contacts the top surface of the first base 50, such that the second evaporating sections 835 are deformed slightly to form the heat pipes 40.

In the process of manufacturing the heat dissipation device, neither soldering flux nor nickel plating is required during assembly of the heat pipes 40 to the fin units 10, 20, 30 and the bases 50, 60. The manufacturing cost of the heat dissipation device is thus minimized, and the manufacturing of the heat dissipation device is simple and convenient.

It is to be further understood that even though numerous characteristics and advantages have been set forth in the foregoing description of embodiments, together with details of the structures and functions of the embodiments, the disclosure is illustrative only; and that changes may be made in detail, especially in matters of shape, size, and arrangement of parts within the principles of the disclosure to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed. 

1. A heat dissipation device, comprising: a first fin unit comprising a plurality of first fins stacked together; a second fin unit located at one side of the first fin unit and comprising a plurality of second fins stacked together; a heat pipe comprising a condensing section extended through the first fin unit and the second fin unit and an evaporating section extending from the condensing section, the evaporating section comprising a first heat absorbing portion extended through the first fin unit and a second heat absorbing portion spaced from the second fin unit; a first base located at one side of the second fin unit and supporting the second heat absorbing portion thereon; and a second base covering the first base, the first and second bases clamping the second heat absorbing portion therebetween.
 2. The heat dissipation device of claim 1, wherein the first base and the second base cooperatively defines a through hole for interference receiving the second heat absorbing portion therein.
 3. The heat dissipation device of claim 2, wherein the first base comprises a first receiving groove for receiving a part of the second heat absorbing portion therein, and the second base comprises a second receiving groove for receiving another part of the second heat absorbing portion therein.
 4. The heat dissipation device of claim 2, wherein the second heat absorbing portion has an ellipse transverse cross-section.
 5. The heat dissipation device of claim 1, wherein the second fin unit defines a receiving a receiving room at a top side thereof, the first base being received in the receiving room.
 6. The heat dissipation device of claim 5, wherein the first fin unit defines a first through hole for the condensing section of the heat pipe interference fitted therein and a second through hole higher than the receiving room, the first heat absorbing portion interference fitted in the second through hole of the first fin unit.
 7. The heat dissipation device of claim 6, further comprising a third fin unit located at one side of the second fin unit which is away from the first fin unit, the third fin unit defining a first through hole for condensing section of the heat pipe interference fitted therein and a second through hole higher than the receiving room, wherein the evaporating section of the heat pipe further comprises a third absorbing portion extending from the second absorbing portion and interference fitted in the second through hole of the third fin unit.
 8. The heat dissipation device of claim 1, wherein the condensing section is parallel to the evaporating section, the heat pipe further comprising a connecting section connected between the condensing section and the evaporating section.
 9. The heat dissipation device of claim 1, wherein each of the first fins comprises a main body, an extending portion extending upward from a middle portion of a top side of the main body, a first flange extending perpendicularly from a bottom side of the main body and a second flange extending perpendicularly from other portion of the top side of the main body except where the extending portion is formed.
 10. The heat dissipation device of claim 9, wherein each of the second fins comprises a main body, a pair of ears extending upward from two opposite ends of a top side of the main body, respectively, a first flange extending perpendicularly from a bottom side of the main body and a pair of second flanges extending perpendicularly from top sides of the ears, respectively.
 11. A method of manufacturing a heat dissipation device, the method comprising: providing a heat pipe comprising an evaporating section and a condensing section, the evaporating section comprising a first heat absorbing portion and a second heat absorbing portion, the second heat absorbing portion having a circular transverse cross section; providing a first fin unit comprising a plurality of first fins stacked together and cooperatively defining a first through hole and a second through hole therein, the heat pipe connected to the first fin unit with the condensing section interference fitted in the first through hole and the first absorbing portion interference fitted in the second through hole; providing a second fin unit comprising a plurality of second fins stacked together and cooperatively defining a first through hole for the condensing section of the heat pipe to be interference fitted therein; providing a first base, mounting the first base on one side of the second fin unit, and supporting the second heat absorbing portion on the first base, with the second absorbing portion of the heat pipe being located above the second fin unit; providing a second base, and covering the second base over the first base to sandwich the second heat absorbing portion between the first base and the second base; and connecting the first and second bases together with a plurality of fasteners, such that the second heat absorbing portion is deformed and clamped between the first base and the second base.
 12. The method of claim 11, wherein the second heat absorbing portion has an ellipse transverse cross section after deformed.
 13. The method of claim 11, wherein the first base and the second base cooperatively defines a through hole for interference receiving the second heat absorbing portion therein.
 14. The method of claim 13, wherein the first base comprises a first receiving groove for receiving a part of the second heat absorbing portion therein, the second base comprises a second receiving groove for receiving another part of the second heat absorbing portion therein, and a sum of depths of the first receiving groove and the second receiving groove is smaller than an outer diameter of the second heat absorbing portion before the second heat absorbing portion is deformed.
 15. The method of claim 11, wherein the second fin unit defines a receiving a receiving room at a top side thereof, the first base being received in the receiving room.
 16. The method of claim 15, wherein the second through hole is higher than the receiving room.
 17. The method of claim 16, further comprising: providing a third fin unit, the third fin unit defining a first through hole and a second through hole higher than the receiving room, wherein the evaporating section of the heat pipe further comprises a third absorbing portion extending from the second absorbing portion; positioning the third fin unit at one side of the second fin unit which is away from the first fin unit; interference fitting the condensing section of the heat pipe in the first through hole of the third fin unit; and interference fitting the third absorbing portion of the heat pipe in the second through hole of the third fin unit.
 18. The method of claim 11, wherein the condensing section is parallel to the evaporating section, the heat pipe further comprising a connecting section connected between the condensing section and the evaporating section.
 19. The method of claim 18, wherein the heat pipe is U-shaped.
 20. The method of claim 11, wherein a plurality of mounting holes are defined in the first base, and a plurality of locating holes are defined in the second base, the fasteners respectively extended through the locating holes and further screwed into the mounting holes for connecting the first base and the second base together. 